gecko-dev/devtools/shared/service-workers-debug-helpe...

68 строки
2.5 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
const Services = require("Services");
const { XPCOMUtils } = require("resource://gre/modules/XPCOMUtils.jsm");
XPCOMUtils.defineLazyServiceGetter(
this,
"swm",
"@mozilla.org/serviceworkers/manager;1",
"nsIServiceWorkerManager"
);
/**
* This helper provides info on whether we can debug service workers or not.
* This depends both on the current multiprocess (e10s) configuration and on the
* usage of the new service worker implementation
* (dom.serviceWorkers.parent_intercept = true).
*
* Since this can be changed on the fly, there are subscribe/unsubscribe functions
* to get notified of this.
*/
const PROCESS_COUNT_PREF = "dom.ipc.processCount";
const MULTI_OPTOUT_PREF = "dom.ipc.multiOptOut";
function addDebugServiceWorkersListener(listener) {
// Some notes about these observers:
// - nsIPrefBranch.addObserver observes prefixes. In reality, watching
// PROCESS_COUNT_PREF watches two separate prefs:
// dom.ipc.processCount *and* dom.ipc.processCount.web. Because these
// are the two ways that we control the number of content processes,
// that works perfectly fine.
// - The user might opt in or out of multi by setting the multi opt out
// pref. That affects whether we need to show our warning, so we need to
// update our state when that pref changes.
// - In all cases, we don't have to manually check which pref changed to
// what. The platform code in nsIXULRuntime.maxWebProcessCount does all
// of that for us.
Services.prefs.addObserver(PROCESS_COUNT_PREF, listener);
Services.prefs.addObserver(MULTI_OPTOUT_PREF, listener);
}
function removeDebugServiceWorkersListener(listener) {
Services.prefs.removeObserver(PROCESS_COUNT_PREF, listener);
Services.prefs.removeObserver(MULTI_OPTOUT_PREF, listener);
}
function canDebugServiceWorkers() {
const isE10s = Services.appinfo.browserTabsRemoteAutostart;
const processCount = Services.appinfo.maxWebProcessCount;
const multiE10s = isE10s && processCount > 1;
const isNewSWImplementation = swm.isParentInterceptEnabled();
// When can we debug Service Workers?
// If we're running the new implementation, OR if not in multiprocess mode
return isNewSWImplementation || !multiE10s;
}
module.exports = {
addDebugServiceWorkersListener,
canDebugServiceWorkers,
removeDebugServiceWorkersListener,
};